[Ni2(ppepO)(C6H5COO)2(CH3COOH)]CIO4*C4H10O: synthesis and characterization of an asymmetric dinuclear nickel(II) complex showing unusual coordination behaviour with relevance to the active site of urease

[Ni2(ppepO)(C6H5COO)2(CH3COOH)]CIO4*C4H10O: synthesis and characterization of an asymmetric dinuclear nickel(II) complex showing unusual coordination behaviour with relevance to the active site of urease